Impact of sedimentation of cloud ice on cloud-top height and precipitation intensity of precipitation systems simulated by a cloud-resolving model

摘要

This study uses a cloud-resolving model to examine the impact of sedimentation of cloud ice on the cloud-top height and the precipitation intensity of typical precipitation systems in East Asia, including a typhoon, snow clouds over the Sea of Japan, and the Baiu front. The fall velocity of cloud ice is assumed to be 0.1 m s~(-1). When the sedimentation process of cloud ice is included in the model, the horizontal distribution and frequency of the cloud-top height show significantly better agreement with satellite observations. Furthermore, cloud ice with sedimentation concentrates at a lower level than that without sedimentation, and converts to snow and graupel by microphysical growth processes. More solid water substances located in the thin layer above the 0°C level contribute to intensification of precipitation at the surface by several percent, especially in the convective area.